This invention relates to a low density, closed cell foamed thermoplastic multi-block copolymer elastomer.
Thermoplastic polymers that have been foamed heretofore were not of sufficiently low density, nor have a substantially uniform cell structure to be entirely satisfactory for the manufacture of components for athletic shoes and other sporting equipment, such as innersoles for shoes and helmet padding nor for use as packaging material for delicate equipment, such as electronic equipment, that is subjected to severe vibrations. Prior art foamed polymers were deficient in strength and the foamed polymers did not have sufficient energy return ratios. The present invention provides a foamed thermoplastic elastomer having a low density, high strength, and a high energy return ratio.